When I first start my Mustang, the idle surges between 500 and 1200 rpms, the charging gauge (stock) jumps all over the place as the idle comes close to dying. All I have to do is give it a good rev and the surge goes away.
This all happened when I upgraded my alt wire and ground wires. I put in a 3g alt last year, but never upgraded the wiring. A few months ago I put in a 4 gauge wire with a 175amp inline fuse, and put a 4 gauge ground wire from the head to the firewall. At the time I also went ahead and checked all my other grounds, cleaned off the metal and secured the grounds. Prior doing the wiring the correct way, I never had this problem. It only started when I upgraded the wiring.
Not quite sure what else to look for...I double checked my grounds and everything seems fine. Possibly the grounding strap being too big, wrong eyelets (copper), too large of a fuse? I am kind of lost at this point.
This all happened when I upgraded my alt wire and ground wires. I put in a 3g alt last year, but never upgraded the wiring. A few months ago I put in a 4 gauge wire with a 175amp inline fuse, and put a 4 gauge ground wire from the head to the firewall. At the time I also went ahead and checked all my other grounds, cleaned off the metal and secured the grounds. Prior doing the wiring the correct way, I never had this problem. It only started when I upgraded the wiring.
Not quite sure what else to look for...I double checked my grounds and everything seems fine. Possibly the grounding strap being too big, wrong eyelets (copper), too large of a fuse? I am kind of lost at this point.